Treatment of yarns comprising keratinous fibers



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TREATMENT OF YARNS COMPRISING KERATINOUS FIBERS N Drawing. Application July 28, 1951,

Serial No. 239,193 i 8 Claims. (Cl. 117-141) The present invention relates to improvements in the art of setting the twist of twisted yarns comprising keratinous fibers. The present invention also relates to twisted yarn-s comprising keratinous fibers, which yarns are characterized by a permanently set twist which is substantially unaffected by the action of hot aqueous solutions. I

-It is known to subject wool and other-animal hairs to the action of such agents as sodium bisulfite, Z-mercaptoethanol and thioglycollic acid so as to reduce the tendency of such fibers to felt, to minimize the degree of damage caused by the attack of moths and carpet beetles and to setthe natural crimp or curl of such fibers. However, the use of such agents for the treatment of yarns made from wool or other animal hairs is not entirely satisfactory as such agents do not give a permanent set to the twist which is put in during the yarn manufacturing operations. Moreover, when such agents are used it is very dificult to control the degree of chemical action on the keratinous material with the result that the treated fibers or yarns vary in their characteristics from batch to batch. In accordance with the present invention, however, the twist in twisted yarns, and particularly highly twisted carpet yarns, comprising keratinous fibers in whole or-in part, is set to a-permanent degree and the twist is substantially unaffected by the action of hot aqueous solutions such as dye baths and the like. Moreover, the method of setting the twist of twisted yarns as practiced in this invention is easily controlled and readily duplicated.

Accordingly, it is one object of the invention to provide improved and readily duplicated methods of permanently setting the twist of twisted yarns comprising keratinous fibers, and particularly wool fibers.

A further'obj'ect of this invention 'is' to provide twisted yarns comprising keratinous fibers, and particularly wool fibers, in which yarns the twist is permanently set and is substantially unaffected by the action of hotaqueous solutions.-

Still further objects and advantages of the invention will appear in the following description and appended claims.

As examples of textile yarns which 'are treated in accordance with this invention are twisted yarns containing wholly or partially such keratinous fibers as sheep wool, lamb wool, alpaca wool, mohair, camel hair, angora wool and the like. The invention is more particularly directed to the treatment of highly twisted carpet yarns fabricated from sheep and/ or lamb wool or mohair fibers.

The methods of this invention are carried out, in general, by impregnating the'twisted textile yarns described above with an aqueous solution of a water-soluble methylated melamine-formaldehyde thermosetting condensation product and one or more water-soluble or water-dispersible organic mercaptan compounds of the class consistingof mercapto aliphatic monohydric alcohols, mercapto aliphatic polyhydric alcohols and mercapto aliphatic carboxylic acids or salts thereof, for a period of time sufficient to wet out the yarns but not'exceeding l0.minutes,

and then subjecting the twisted textile yarns to a curing 2 operation with or without the accelerating action of a catalytic agent.

Water-soluble methylated melamine-formaldehyde thermosetting resins for use in the methods of this invention are suitably prepared by first reacting about 1 molecular proportion of melamine with about 3 to 6 mols of formaldehyde or a compound capable of forming formaldehyde in the reaction medium as, for example, paraformaldehyde, in a neutral to alkaline aqueous medium until a monomeric or low polymeric melamine: formaldehyde condensation product which is water-soluble and capable of infinite dilution with water is obtained, after which from 10 to molecular proportions of methanol are added to the solution. The solution is next acidified with an acid, preferably a mineral acid such as hydrochloric acid or phosphoric'acid and the reaction is allowed to proceed until an aqueous solution of a monomeric or low polymeric methylated melamine formaldehyde condensation product which is infinitely dilutable with water is obtained. The solution is then neutralized with an alkaline compound such as an alkali metal hydroxide or carbonate. The resulting solution may be concentrated, if desired, by heating it to a temperature between about and F. under a vacuum. I The invention is particularly directed to the use of mercapto monohydric alcohols or polyhydric alcohols, as,

' for example, 2-mercapto-ethanol, Z-mercapto-propanol, 3-

mercapto-propanol, l-thiosorbitol, l-thioglycerol and the like. One or more of such mercapto alcohols may be employed. It is preferable tofemploy a mercapto alcohol which is at least soluble to the extent of 1% by weight in i an aqueous medium and more particularly such alcohols which are relatively inactive at room temperatures and which will not precipitate the condensation product from the solution. 2-mercapto-ethanol, l-thiosorbitol and lthioglycerol are particularly suitable when employed with the methylated melamine-formaldehyde condensation products in an aqueous medium.

-As examples of mercapto aliphatic carboxylic acids which are employable in the methods of this invention may be mentioned thioglycollicacid, a-mercapto propionic acid, fi-mercapto. propionic acid, .a-mercapto butyric acid and the like, and water-soluble or finely water-dispersible alkali metal, alkaline earth metal or ammonium salts thereof. ,This'invention is more particularly directed to the use of theammonium salts of such acids in an aqueous treating medium and in such instancesthe salt per so can be added to the medium. or. the ammonium salt may be formed in situ in the aqueous medium prior to the textile treatment by adding the acid to an aqueous medium contarmng ammonia. The latter procedureis preferred and in forming the ammonium saltin situ the quantity or proportion of ammonia used is preferably either limited to the minimum necessary to cause solution ofthe acid or is limited to a maximum-ofthat which would raise the hot plate cure time of the condensation-product above 1 minute in the absence of a catalyst.

In carrying out the treatment of twisted textile yarns comprising keratinous fibers of the type hereinbefore described, the aqueous medium may comprise inaddition to the above described condensation products and organic mercapto compounds suitable adjuvants such as catalysts, wetting agents and the like. It is possible to use a wide variety of catalysts to accelerate the curing of the con-. densation products after they have been applied to the textile material. As examples of those which are'employ able herein may be mentioned zinc chloride, diammonium hydrogen phosphate, the mineral acid salts of amino alcohols such as Z-amino-Z-methyl propanol hydrochloride and the like. When wetting agents are also employed -it is preferable 'touseanionic. or non-ionic com pounds as, for example, sodium salts of sulfonated aromatic compounds having along chain substituted alkyl group, long chain polyethylene oxides and derivatives thereof, aryl alkyl polyether alcohols, aliphatic polyether alcohols and thelike.

A further understanding of the invention will be obtained from the following examples which are intended to be illustrative, but not limitative ofthe scope of the invention, parts and percentages being by weight unless otherwise specified.

Example I A methylated melamine-formaldehyde thermos ettin'g condensation product was first prepared by reacting 1 tool of melamine with 5 mole of formaldehyde in the form of a 37% neutral aqueous solution at a temperature of about 100 until solution occurred, after which the melamine-formaldehyde condensation product was separated from the solution by cooling and then removed from the solution by filtration. The condensation product thus obtained was next dried and then reacted with 14 mols of methyl alcohol under refluxing conditions in the pres- 'ence of about 0.1 11101 of hydrochloric acid until solution occurred whereupon the solution was neutralized with caustic soda to the phenolphthalein endpoint. The resulting solution was concentrated by evaporation until it contained 60% condensation product solids. This solution was in the form of a viscous liquid capable of extreme dilution with water and/or alcohol without preeipitating the methylated melamine-formaldehyde condensation product therein.

A treating bath was prepared by stirring the following ingredients 's tpans of the 60% solution of methylated melamineformaldehyde condensation product prepared as de- V scribed immediately above \86 parts of water 3 parts of 2-mercapt'o-ethanol 0.5 part of sodium cetyl benzene 'sulfo'n'ate v 2 parts of 2-amino2-rnethyl propanol phosphate (preparing by neutralizing 2-a'mino-2-n1e'thyl propanol with phosphoric acid) A skein of highly twisted and dyed all wool carpet yarn was immersed in the above solution for a period of 1 minute and then immediately removed from the solution and centrifuged until it retained 14% condensation product solids. The skein of yarn was next heated to a term perature of 300 F. until dry and finally heated at the same temperature for an additional 15 minutes to render the condensation product therein water-insoluble.

The above treatment did not afiec't the dye shade of the yarn. Moreover, the twist in the yarn was not affected by carpet shampooing or by a 5 minute dip in a hot aqueous solution, that is, the yarn did not untwist as a result of such treatments.

Example II A treating bath was prepared by stirring the following t ingredients in the order named:

parts of the 60% solution of methylated melamine formaldehyde condensation product prepared as described in the first paragraph of Example I 90 parts of water 0,1 part of ammonia water (speeific ravit eosm 2 parts of thiog'lycollic acid (70% acid) A skein of highly twisted all mohair yarn was immersed in the abofve solution for a period of 2 minutes and then immediately removed from the solution and centrifuged until it retained about 12% condensation product solids. The resulting yarn was then heated for minutes at a temperature of 300 F. to cure the condensation product therein to the water-insoluble state.

Any suitable methodmay be used for impregnating or wetting out the yarns in the aqueous compositions em ployed herein, for example, simple immersion, padding Cir 4 the material through the composition or the like. In addition, excess solution may be removed from the impregnated yarns by any of the well-known means such as hydroextraction, hand wringing, squeeze rolls and the like.

It is generally preferable in carrying out the invention to deposit from 5 to 20% by weight of the condensaation product on the yarn containing keratinous fibers, based on the dry weight of the yarn. Moreover, it is preferable to ,deposit from about 5 to 20% of an aliphatic mercapto carboxylic acid or salts thereof, or from about 10 to 50% of an aliphatic mercapto mon'o'hydric or polyhydric alcohol on the material based on the weight of the condense tion product deposited.

It is generally desirable to cure the condensation product at temperatures within the range of 225 to 350 F. However, when curing temperatures below 300 F. are employed it is generally necessary to cure for longer periods of time and temperatures between 300 and 350 F. are preferred since a more rapid cure is etfected. The term cure as used herein is intended to mean an operation during which the condensation product is polymerized and rendered substantially water-insoluble.

This application is a continuation-in-part of our co- V pending application Serial No. 788,658, filed on November 28, 1947, now abandoned.

What is claimed is:

l. Amethod of setting the twist of twisted yarns com- .prising keratinous fibers which comprises immersing said yarns for a period of time sufficient to wet out the yarns but not exceeding 10 minutes in an aqueous solution of water-soluble methylated melamine-formaldehyde thermosetting condensation product and an organic mercapto compound selected from the group consisting of watersoluble and water-dispersible mercapto aliphatic monohydric alcohols, mercapto aliphatic polyhydric alcohols, mercapto aliphatic carboxylic acids and salts of said acids, said condensation productand mercapto compound 'beingsupplied in an amount sufficient to deposit from 5 to 20% by weight of said condensation product, based on the dry yarns, and from 5 to 50% of said mercapto compound, based on the condensation product, immedir ately thereafter removing the yarns from said solution and then subjecting said yarns to elevated temperatures to cure said condensation product.

2. A method of setting the twist of twisted yarns com prising keratinous fibers which comprises immersing said yarns for a period of time suificient to Wet out the yarns but not exceeding 10 minutes in an aqueous solution of a water-soluble methylated melamine-formaldehyde ther mosetting condensation product and 2-mercapto ethanol, said solution being infinitely dilutable with water, imme diately thereafter removing said yarns from the solution, extracting the yarns to remove excess solution therefrom, the concentration of the solution and the degree of extraction being adjusted to deposit from 5 to 20% by weight of said condensation product, based on the dry yarns, and from 10 to 50% by Weight of said Z-mercapto ethanol, based on the condensation product, and then subjecting said yarns to elevated temperatures to cure said condensation product. I e I 3. A method according to claim 2, but further char; acterized in that the yarns are highly twisted all wool yarns.

4. A method of setting the twist of twisted yarn comprising keratinous fibers which comprises immersing said yarns for a period of time sufficient to wet out the yarns but not exceeding 10 minutes in an aqueous solution of a water-soluble methylated melamine-formaldehyde thermosetting condensation product and l-thiosorbitol, said solution being infinitely dilutable with Water, immediately thereafter removing said yarns from the solution, extract ing the yarns to remove excess solution therefrom, the concentration of the solution and the degree of extraetion being adjusted to deposit from 5 to 20% by weight of said condensation product, based on the dry yarns, and from to 50% by weight of said l-thiosorbitol, based on said condensation product, and then subjecting said yarns to elevated temperatures to cure said condensation product.

5. A method according to claim 4, but further characterized in that the yarns are highly twisted all wool yarns.

6. A method of setting the twist of twisted yarn comprising keratinous fibers which comprises immersing said yarns for a period of time sufiicient to wet out the yarns but not exceeding 10 minutes in an aqueous solution of a water-soluble methylated melamine-formaldehyde thermosetting condensation product and the ammonium salt of thioglycollic acid, said solution being infinitely dilutable with water, immediately thereafter removing said yarns from the solution, extracting the yarns to remove excess solution therefrom, the concentration of the solution and the degree of extraction being adjusted to deposit from 5 to 20% by weight of said condensation product, based on the dry yarns, and from 5 to 20% of said salt, based on said condensation product, and then subjecting said yarns to elevated temperatures to cure said condensation product.

7. A method according to claim 6, but further characterized in that the yarns are highly twisted all wool yarns.

8. A method of setting the twist of twisted yarns comprising keratinous fibers which comprises immersing said yarns for a period of time sufficient to wet out the yarns but not exceeding 10 minutes in an aqueous solution of water-soluble methylated melamine-formaldehyde thermosetting condensation product, a catalyst for accelerating the cure of said condensation product and an organic mercapto compound selected from the group consisting of water-soluble and water-dispersible mercapto aliphatic monohydric alcohols, mercapto aliphatic polyhydric alcohols, mercapto aliphatic carboxylic acids and salts of said acids, said condensation product and mercapto compound being supplied in an amount sufiicient to deposit from 5 to 20% by weight of said condensation product, based on the dry yarns, and from 5 to of said mercapto compound, based on the condensation product, immediately thereafter removing the yarns from said solution and then subjecting said yarns to elevated temperatures to cure said condensation product.

References Cited in the file of this patent UNITED STATES PATENTS 1,930,646 Gray et a1 Oct. 17, 1933 1,940,730 Platt Dec. 26, 1933 2,039,228 Kratz et a1 Apr. 28, 1936 2,238,672 Arthur et a1 Apr. 15, 1941 2,285,852 Cornwell et a1 June 9, 1942 2,329,622 Johnstone et al. Sept. 14, 1943 2,622,996 Cohen Dec. 23, 1952 

1. A METHOD OF SETTING THE TWIST OF TWISTED YARNS COMPRISING KERATINOUS FIBERS WHICH COMPRISES IMMERSING SAID YARNS FOR A PERIOD OF TIME SUFFICIENT TO WET OUT THE YARNS BUT NOT EXCEEDING 10 MINUTES IN AN AQUEOUS SOLUTION OF WATER-SOLUBLE METHYLATED MELAMINE-FORMALDEHYDE THERMOSETTING CONDENSATION PRODUCT AND AN ARGANIC MERCAPTO COMPOUND SELECTED FROM THE GROUP CONSISTING OF WATERSOLUBLE AND WATER-DISPERSIBLE MERCAPTO ALIPHATIC MONOHYDRIC ALCOHOLS, MERCAPTO ALIPHATIC POLYHYDRIC ALCOHOLS, MERCAPTO ALIPHATIC CARBOXYLIC ACIDS AND SALTS OF SAID ACIDS, SAID CONDENSATION PRODUCT AND MERCAPTO COMPOUND BEING SUPPLIED IN AN AMOUNT SUFFICIENT TO DEPOSIT FROM 5 TO 20% BY WEIGHT OF SAID CONDENSATION PRODUCT, BASED ON DRY YARNS, AND FROM 5 TO 50% OF SAID MERCAPTO COMPOUND, BASED ON THE CONDENSATION PRODUCT, IMMEDIATELY THEREAFTER REMOVING THE YARNS FROM SAID SOLUTION AND THEN SUBJECTING SAID YARNS TO ELEVATED TEMPERATURES TO CURE SAID CONDENSATION PRODUCT. 